In the field of test and measurement, a device typically collects sample data from one or more electrical test points over some period of time, whereby the value of a sample represents the voltage level of the given test point at a specific point in that timeline. Samples collected in one time-contiguous sequence are commonly considered as a single acquisition. Common tools in this field today include logic analyzers and digital storage oscilloscopes, such as those manufactured by Agilent Technologies, Tektronix Inc., and LeCroy Corp. These systems typically have a dedicated hardware platform, an attached personal computer coupled to the logic analyzer, or a digital storage oscilloscope, operating in accordance with software that can collect, store, and manipulate the data representing sample data over one or more signal channels, and renders such to the user in a pseudo real-time or non real-time fashion on a display. These systems commonly display the data to the user on the display as a two-dimensional graph, whereby the x-axis represents time, and the y-axis value describes the voltage of the test point at that time for a particular signal channel, as illustrated for example in FIG. 1. The user relies on this data representation to gain insight into the operation of the unit under test, thereby allowing detection of errors, anomalies, or proof that the device is operating properly.
Although the typical two dimensional voltage versus time graph is useful for showing one sample per channel per column of pixels on the display, variations in repetitive waveforms over time are difficult to discern. Further, as devices under test become more complex and the number of channels in acquisition devices available to the user rises, the sampling rates of signals by acquisition devices results in a huge amount of data over multiple channels in the memory of the computer system or digital oscilloscope storing such data. As a result, it becomes problematic to render the large amount of data from multiple channels in test and measurement systems all at once on a display to the viewer in a meaningful manner, thereby making it more difficult for the user to visualize and identify data of interest at a particular channel, and especially among multiple channels.
Approaches to improve rendering of two-dimensional voltage time graphs are described for example in U.S. Pat. Nos. 6,151,010 and 7,216,046, which enables common persistence modes via overlays or density maps of a channel on a digital oscilloscope. A drawback of this approach is that it is difficult to obverse patterns occurring in the channel. In U.S. Patent Application No. 2003/0006990, a digital oscilloscope displays waveform variations over time as a surface map graph. Such rendering is limited to a single channel at a time without correlation with any other channels. U.S. Patent Application Publication No. 2005/0234670 describes viewing multiple channels, domains, or acquisitions simultaneously, but does not provide for a display of multiple channels and acquisitions (or domains) simultaneously in a single three-dimensional view on a display. Further, the systems described in the above cited patents and publication have limited flexibility in the organization and presentation of the data on a display, which restricts the user's ability to quickly visualize and compare data when analyzing complex systems.